Electrically anesthetizing a peripheral nerve with on-demand electrical nerve block for chronic pain management

ABSTRACT

Chronic pain management can be achieved by electrically anesthetizing a peripheral nerve with on-demand electrical nerve block (OD-ENB). OD-ENB can be provided by an implantable capsule. Externally, at least a portion of the capsule can be constructed of a conductive membrane and the rest of the capsule comprises a biocompatible material. A blocking electrode contact, a return electrode contact, and a powering/communication component can be within the capsule. The blocking electrode contact can deliver a direct current (DC) through a portion of the conductive membrane to block conduction in the neural tissue to provide the OD-ENB. The return electrode contact can receive a return current from the neural tissue through another portion of the conductive membrane. The powering/communication component can communicate with one or more external components located external to the patient&#39;s body to receive a power signal. Notably the capsule has no internal battery.

RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application Ser.No. 62/818,857, filed Mar. 15, 2019, entitled “ELECTRICALLYANESTHETIZING A PERIPHERAL NERVE FOR THE TREATMENT OF CHRONIC PAIN ANDOTHER DISORDERS”. The entirety of this provisional application is herebyincorporated by reference for all purposes.

TECHNICAL FIELD

The present disclosure relates generally to chronic pain management and,more specifically, to electrically anesthetizing a peripheral nerve withon-demand electrical nerve block (OD-ENB) for chronic pain management(and/or the treatment of other disorders).

BACKGROUND

Chronic pain management is a complicated and highly patient specificarea of medicine. One example of a disorder that causes chronic pain isKnee Osteoarthritis (KOA), a degenerative joint disease, common in boththe elderly and in the obese. Conservative treatments for KOA includeweight loss, exercise, analgesics, intra-articular steroid injectionsand physical therapy. More radical treatments include surgicalinterventions, like knee arthroplasty, which can itself result insignificant persistent pain. Moreover, there are many patients that arenon-responsive to the conservative treatment, but are not good surgicalcandidates because of medical comorbidities and/or a high body massindex (BMI). Such KOA patients are highly susceptible to chronic opioiduse. The use of opioids for chronic pain has led to a nationwideepidemic of addition resulting, in the implosion of families andcommunities.

Accordingly, clinicians seek alternative interventions in patients thathave failed conservative therapy and/or in patients in which surgicalinterventions do not work. One option for these patients is genicularnerve block (GNB) targeting the sensory and motor nerves to thestructures around the knee with an injection of corticosteroid and localanesthetic under ultrasound guidance. In such patients, improvements canbe seen for up to six months post-injection and the procedure can berepeated, but only at a physician's office. Another option for thesepatients is radiofrequency ablation of the genicular nerves, but eachpatient has different outcomes and the progression of their disease andrecovery from the ablation procedure is highly individualized. Thesetreatment modalities are ill suited to address the needs of patients interms of adequate pain relief, quality of life, and convenience, makingpatients feel as if their pain management is out of their control.

SUMMARY

The present disclosure relates to electrically anesthetizing aperipheral nerve with on-demand electrical nerve block (OD-ENB) forchronic pain management (and/or the treatment of other disorders).OD-ENB is a patient-specific intervention that can be adjusted over timeto provide sustained relief for a long period of time and iscustomizable for the individual patient, giving patients control oftheir pain management without opioids.

In an aspect, the present disclosure can include a system that can beused to electrically anesthetize a peripheral nerve with on-demandelectrical nerve block (OD-ENB) for chronic pain management. The systemcan include a power source and an implantable capsule. At least aportion of the capsule can be constructed of a conductive membrane andthe rest of the capsule can be constructed of a biocompatible material.The capsule can include (within the capsule) a blocking electrodecontact, a return electrode contact, and a powering/communicationcomponent. The blocking electrode contact can be configured to deliver adirect current (DC) through a portion of the conductive membrane. The DCcan be configured to block conduction in the neural tissue to provideOD-ENB, either cathodic or anodic. The return electrode contact can beconfigured to receive a return current from the neural tissue throughanother portion of the conductive membrane. The powering/communicationcomponent can be configured to communicate with the power source toreceive a power signal.

In another aspect, the present disclosure can include a method forelectrically anesthetizing a peripheral nerve with OD-ENB for chronicpain management. The method can include wirelessly powering a capsulewithin a patient's body with a power signal from an external powersource (which can power a plurality of capsules, in some embodiments).At least a portion of the capsule can be constructed of a conductivemembrane, while the rest of the capsule can be constructed of abiocompatible material. The capsule can include a blocking electrodecontact configured to deliver a DC through a portion of the conductivemembrane, wherein the DC is configured to block conduction in the neuraltissue to provide OD-ENB; a return electrode contact configured toreceive a return current from the neural tissue through another portionof the conductive membrane; and a powering/communication componentconfigured to communicate with the external power source to receive thepower signal. The method can also include delivering the DC from theblocking electrode contact to the neural tissue for a time. The DC canbe configured to cause the OD-ENB (either a cathodic block or an anodicblock).

In still another aspect, the present disclosure can include aneuromodulation device that can be used to electrically anesthetize aperipheral nerve with on-demand electrical nerve block (OD-ENB) forchronic pain management. The neuromodulation device can include animplantable capsule, at least a portion of which can be constructed of aconductive membrane and the rest of the capsule can be constructed of abiocompatible material. The capsule can include within the capsule, ablocking electrode contact, a return electrode contact, and apowering/communication component. The blocking electrode contact can beconfigured to deliver a DC through a portion of the conductive membrane.The DC can be configured to block conduction in the neural tissue toprovide OD-ENB (either a cathodic block or an anodic block). The returnelectrode contact can be configured to receive a return current from theneural tissue through another portion of the conductive membrane. Thepowering/communication component can be configured to communicate withone or more external components located external to the patient's body.One of the one or more external components can include an external powersource that sends a power signal to the neuromodulation device that hasno internal battery. The one or more external components can be used forpowering/communication with a plurality of capsules.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other features of the present disclosure will becomeapparent to those skilled in the art to which the present disclosurerelates upon reading the following description with reference to theaccompanying drawings, in which:

FIG. 1 is a schematic diagram showing an example of a system that can beused to electrically anesthetize a peripheral nerve with on-demandelectrical nerve block (OD-ENB) for chronic pain management inaccordance with an aspect of the present disclosure;

FIG. 2 shows an example of the power/communications component of FIG. 1; and

FIG. 3 is a process flow diagram illustrating a method for electricallyanesthetizing a peripheral nerve with OD-ENB for chronic pain managementin accordance with another aspect of the present disclosure.

DETAILED DESCRIPTION

I. Definitions

Unless otherwise defined, all technical terms used herein have the samemeaning as commonly understood by one of ordinary skill in the art towhich the present disclosure pertains.

As used herein, the singular forms “a,” “an” and “the” can also includethe plural forms, unless the context clearly indicates otherwise.

As used herein, the terms “comprises” and/or “comprising,” can specifythe presence of stated features, steps, operations, elements, and/orcomponents, but do not preclude the presence or addition of one or moreother features, steps, operations, elements, components, and/or groups.

As used herein, the term “and/or” can include any and all combinationsof one or more of the associated listed items.

As used herein, the terms “first,” “second,” etc. should not limit theelements being described by these terms. These terms are only used todistinguish one element from another. Thus, a “first” element discussedbelow could also be termed a “second” element without departing from theteachings of the present disclosure. The sequence of operations (oracts/steps) is not limited to the order presented in the claims orfigures unless specifically indicated otherwise.

As used herein, the term “on-demand electrical nerve block (OD-ENB)” isa means of electrically anesthetizing a peripheral nerve for thetreatment of chronic pain and other disorders. OD-ENB can provide apatient the ability to suppress their pain symptoms (or symptoms ofother disorders) immediately with no systemic side effects other thaninactivation of the targeted nerve. The treatment is completelynon-addicting and provides an alternative to pharmacological treatments.Additionally, dosing is not limited because there are no dose-relatedtoxicity effects.

As used herein, the terms “electrical block”, “electrical nerve block”,“nerve conduction block”, and “nerve block” (as well as variationsthereof) can refer to the attenuation of conduction in one or morenerves within target neural tissue by a purposeful interference withnerve activation. The interference with nerve activation can be due to achange in the electric field caused by application of an electricalsignal (to the neural tissue. Attenuating conduction can refer toextinguishing 100% (complete block) or less (partial block) (e.g., 90%,80%, 70%, 60%, 50%, or the like) of the action potentials travelingthrough the target neural tissue. In some instances, the electricalblock can be can be partial or complete and reversible. The electricalblock can be a “hyperpolarization block” or a “depolarization block”.

As used herein, the term “electrical signal” can refer to a time-varyingvoltage or current. As an example, the electrical signal can transmit adirect current (DC). For example, “DC block” can refer to theapplication of a DC pulse with an amplitude and polarity configured tocause a change in electric field (to depolarize or hyperpolarize)sufficient to alter conduction in the nerve.

As used herein, the term “direct correct (DC)” can refer to a type ofelectrical signal that includes a unidirectional flow of electric charge(e.g., varying in time, not amplitude). For example, the DC can have aplateau of a cathodic polarity or an anodic polarity. However, in someinstances, at least a portion of the amplitude may vary—for example, theDC can further be represented as a waveform that includes a ramp from azero position to the plateau and may also include a ramp down from theplateau position to the zero position. As another example, the waveformcan include a subsequent plateau of the opposite polarity (in suchcases, the waveform can be a biphasic waveform with the second phaseconfigured to reduce charge either as a charge balanced waveform or acharge imbalanced waveform). The waveform can also include ramps fromzero to the plateau and/or from the plateau to zero.

As used herein, a “waveform” can refer to a graphical representation ofchanges in current or voltage over time.

As used herein, the term “hyperpolarization block” or “anodic block” canrefer to the cessation of nerve signaling in one or more nerves withintarget neural tissue caused by the accumulation of negative chargesand/or loss of positive charges within a cell, lowering its membranepotential below its resting potential. For example, an influx ofnegative chloride ions or a loss of positive potassium ions can preventthe activation gates of voltage-gated sodium channels from opening,making action potentials more difficult to generate. An anodic(negatively charged) current can be used to cause a hyperpolarizationblock.

As used herein, the term “depolarization block” or “cathodic block” canrefer to the cessation of nerve signaling in one or more nerves withintarget neural tissue caused by the accumulation of certain positivelycharged ions within a cell. For example, increased intracellularpotassium ion levels can close inactivation gates in voltage-gatedsodium channels within the cellular membrane, such that the movement ofsodium into the cell is reduced and action potentials are inhibited. Acathodic (positively charged) current can be used to cause adepolarization block.

As used herein, the term “polarity” can refer to a direction of electronmovement. For example, the polarity can be cathodic (positively charged)or anodic (negatively charged).

As used herein, the term “nerve” can refer to at least one or morefibers (e.g. axons) of nerve cells that employ electrical and chemicalsignals to transmit motor, sensory, and/or autonomic information fromone body part to another. A nerve can refer to a component of thecentral nervous system and/or the peripheral nervous system.Additionally, one or more nerves can make up neural tissue.

As used herein, the terms “nerve activity” and “neural activity” canrefer to signaling (conduction) and activation patterns to transmitneural signals carrying neural information.

As used herein, the term “conduction” can refer to movement of chargedparticles through space (e.g., a nerve fiber), forming an electricalcurrent. Electrical block can be used to attenuate conduction throughone or more nerves.

As used herein, the term “amplitude” can refer to a measurement of thedependent variable (e.g., current, voltage, etc.) above or below zero.

As used herein, the term “electrode contact” can refer to a materialacting as a conductor through which electricity enters or leaves. Atleast a portion of the material can be a biocompatible material.

As used herein, the term “coil” can refer to an electric circuit elementwith one or more turns, usually roughly circular or cylindrical, ofcurrent-carrying wire designed to produce a magnetic field or provideelectrical resistance or inductance.

As used herein, the terms “subject” and “patient” can be usedinterchangeably and refer to any warm-blooded organism including, butnot limited to, a human being, a pig, a rat, a mouse, a dog, a cat, agoat, a sheep, a horse, a monkey, an ape, a rabbit, a cow, etc.

II. Overview

Chronic pain management is a complicated and highly patient specificarea of medicine. Current pain management treatment modalities caninclude lifestyle changes, physical therapy, analgesics, opioids,anesthetic nerve block, radiofrequency ablation, and radical surgery.Current treatment modalities are ill suited to address the needs ofpatients in terms of at least adequate pain relief, quality of life, andconvenience. Patients often feel as if their pain management is out oftheir control. There is a need for an effective pain treatment thatallows patients to control their pain management, giving pain reliefimmediately when it is needed without having to visit a medical facilityand without the use of addictive opioids.

The present disclosure describes devices, systems, and methods thatprovide on-demand electrical nerve block (OD-ENB), a self-administeredpatient specific treatment modality. OD-ENB is a treatment modality thatgives immediate pain relief, so OD-ENB is well-suited for chronic painmanagement, but OD-ENB can also be used in the treatment of otherdisorders. OD-ENB is fast acting, reversible, non-addictive,localizable, titratable, non-addictive treatment modality that gas noside effects. Most notably, OD-ENB is minimally invasive, including anexternal device that includes a power source and an implantable capsulethat receives power from the power source (e.g., through an inductivecoupling that allows for communication and power transfer) and includesan electrode configuration to deliver a direct current to achieve thenerve block. The electrode configuration includes a blocking electrodecontact configured to deliver the DC to block conduction in the neuraltissue and a return electrode contact configured to receive a returncurrent. The implantable capsule does not include an internal battery,allowing the size of the capsule to be reduced. It should be noted thatexternal component can be used for powering/communication with aplurality of capsules (e.g., to provide a complete block to one or morenerves).

III. Systems

An aspect of the present disclosure can include a system 10 (FIG. 1 )that can provide on-demand electrical nerve block (OD-ENB), which can beused for chronic pain management (and the treatment of other disorders).OD-ENB is a means of electrically anesthetizing a portion of neuraltissue (that includes a peripheral nerve of interest), which can be usedto treat a wide range of patients (spanning from younger individuals whoare trying to maintain an active lifestyle to elderly individuals withpotentially complicated medication needs). Due to the complicated natureof pain, it is difficult to find a solution that fits all patients, butOD-ENB is well suited to address the need for adequate pain relief ofthis wide spectrum of patients because OD-ENB can be customized in termsof dosage and/or location, providing adequate pain relief, quality oflife, and convenience. Accordingly, OD-ENB gives patients the feelingthat their pain management is controllable, since OD-ENB provides thepatient the ability to immediately suppress pain symptoms. Further,because OD-ENB is based on the fundamental principle of electrical nerveblock, there are no systemic side-effects other than the inactivation ofthe targeted nerve. The treatment is completely non-addicting and thusprovides an excellent alternative to pharmacological treatments. Inaddition, dosing with the ON-ENB system is not limited because there areno dose-related toxicity effects. The OD-ENB can be provided using a DCwaveform without production of irreversible Faradaic reaction productsat the neural tissue via manipulation of the DC waveform and/or theelectrode material.

The system 10 includes a neuromodulation device (referred to as animplantable capsule 11) and one or more external device(s) 12. Thecapsule 11 can be implanted at a distance under the patient's skin inproximity to a nerve of interest (e.g., including sensory nerves, like Cfibers or other fibers associated with pain) to provide localized nerveblock. In some instances, the capsule 11 can be injected into thepatient's body next to the nerve of interest. The pain can be associatedwith any type of pain in the patient's body. Non-limiting examples canbe pain associated with knee osteoarthritis (KOA), shoulder pain, painassociated with hernia repair, pelvic pain, and the like. The nerve ofinterest (or target nerve) related to these non-limiting examples caninclude the genicular nerve, the axillary nerve, the suprascapularnerve, the ilioinguinal nerve, the iliohypogastric nerve, the pudendalnerve, or the like.

The capsule 11 can be of a small size so that it can be implantedwithout substantially disrupting the patient's comfort. Additionally, atleast a portion of the external shell of the capsule 11 can be made ofone or more substantially biocompatible materials (e.g., at least aportion of the external shell can be made of a conducting portion, suchas a biocompatible composite membrane). For example, the capsule 11 canbe miniature. In some instances, the size of the capsule 11 can be smallbecause the capsule 11 does not include an internal battery. In theseinstances, the capsule 11 can be externally powered under control of thepatient by a power source, which can be one of the one or more externaldevice(s) 12. In some instances, the one or more external components canbe used for powering/communication with a plurality of capsules.

At least a portion of the capsule 11 can be configured to deliver adirect current (DC) to the target nerve to deliver a DC block (e.g.,through a blocking electrode contact 13). For block, the DC can have anamplitude that is at least a block threshold. The block threshold fordifferent types of nerves of different sizes may be different. The DCused for block can be cathodic (positively charged) with a cathodicamplitude of at least the cathodic block threshold or anodic (negativelycharged) with an anodic amplitude of at least the anodic blockthreshold. The DC block can be provided as hyperpolarization block ordepolarization block. Hyperpolarization block is caused by theaccumulation of negative charges and/or loss of positive charges withina cell, lowering its membrane potential below its resting potential,caused by an anodic current. Depolarizing block is caused by theaccumulation of certain positively charged ions within a cell, caused bya cathodic current. The DC used for block can be administered for atime. As a non-limiting example, the time can be more than 2 minutes. Asanother non-limiting example, the time can be more than 5 minutes. Asyet another non-limiting example, the time can be more than 10 minutes.

The DC can be generated as a DC waveform with a shape that facilitatesthe DC block. In some instances, the generated DC waveform can have ananodic polarity or a cathodic polarity, and an amplitude sufficient tocause the DC block. As an example, the DC block can be delivered by amonophasic waveform or a biphasic waveform. As a further example, thewaveform can have a ramp to the cathodic or anodic block threshold. Insome instances, the properties of the DC waveform can be manipulated sothat block can occur uninterrupted during the equal and oppositerecharge phase.

The capsule 11 can include a blocking electrode 15 and a blockingelectrode contact 13, a return electrode 16 and a return electrodecontact 14, and a powering/communications component 18. In someinstances, the blocking electrode 15 and the return electrode 16 can besub-capsules within the larger capsule 11 that at least partiallyenclose the blocking electrode contact 13 and the return electrodecontact 14. The sub-capsules include materials necessary for theelectrode (e.g., saline, an ionically conductive medium, a high chargecapacity material, a high capacitance slurry material, etc.). It shouldbe noted that in some embodiments, the materials necessary for theblocking electrode 15 may be different from those required by the returnelectrode 16. For example, at least the blocking electrode 15 can bedesigned as described in at least one of U.S. Pat. Nos. 9,008,800,9,496,621, WO 2019/133783, WO 2019/133784, U.S. Pat. Nos. 9,387,322, or10,195,434, which are incorporated herein by reference. In any of theseexamples, the electrode can convert the DC waveform into an ionicsignal, which can be delivered to the target nerve by the blockingelectrode contact 13. The blocking electrode contact 13 and the returnelectrode contact 14 can be located in any position in the capsule 11.For example, the blocking electrode contact 13 and the return electrodecontact 14 can be located on the same side (e.g., next to each other) oron different sides (e.g., opposite one another) of the capsule 11. Thesub-capsules can be connected by a channel 17 with a valve forrecharging. In some instances, the valve of the channel 17 can be amicrofluidic valve that can be used to provide a path for recharge sothat the recharge can occur at a higher amplitude, resulting in ashorter recharge duration.

At least a portion of the external shell of the capsule can be made of aconducting portion, such as a biocompatible composite membrane. In someinstances, the conducting portion can separate material(s) of theelectrode from the tissue, while providing ionic conduction through themembrane. The conducting portion can be from 20% to 100% of the externalshell. In some instances, the conducting portion can be noncontiguous.The remaining portion of the external shell can be a non-conductive orminimally-conductive biocompatible material. Additionally, the blockingelectrode contact 13 and the return electrode contact 14 can beconfigured to deliver the DC to the nerve and receive the return currentfrom the nerve through at least respective portions of the conductivemembrane.

The powering/communications component 18 can be configured tocommunicate with one or more external component(s) 12 located externalto the patient's body. Although not shown herein, the one or moreexternal components 12 can be used for powering/communication of aplurality of capsules.

As an example, both the powering/communications component 18 and the oneor more external component(s) can each have an inductive coil forcommunication and/or power transfer of an inductive power signal. Atleast one of the one or more external component(s) 12 can include anexternal power source that sends a power signal to thepowering/communications component 18. The powering/communicationscomponent 18 is shown in greater detail in FIG. 2 , in which thepowering/communications component 18 includes a communications component21, a demodulator 22, a power transfer component 23, a microcontroller24 with commands 25 and controls 26, as well as an electrical component27.

The communications component 21 can be configured to communicate withthe one or more external device(s) 12 outside of the patient's body. Insome instances, the communications component 21 can be an inductive coilthat is configured to communicate with an inductive coil located outsidethe patient's body. The communications component 21 can receivecommands, like DC block set point commands and wireless power (orenergy). The DC set point commands can go through the demodulator 22 tothe microcontroller 24, which interprets the DC set point commands andsets commands 25 and controls 26 accordingly. The wireless power can bereceived by the power transfer component 23, which has a power transferrectifier, shunt rectifier, and other components, and sent to theelectrical component 27. Based on the wireless power, as well as the setpoint commands 25 and controls 26, the electrical component canconfigure the DC and deliver the DC to the blocking electrode 15 and/orthe blocking electrode contact 13 for delivery to the neural tissue.Accordingly, the electrical component 27 can be coupled to thecommunications component 21 and the blocking electrode 15 and/orblocking electrode contact 13. In some instances, the electricalcomponent can also be coupled to the return electrode 16 and/or thereturn electrode contact 14. The electrical component 27 can include acurrent-to-voltage charge pump-converter that can multiply the receivedvoltage to provide enough compliance voltage for constant DC nerve blockcurrent. A switch network can be used to change DC block polarity ifnecessary and to periodically shunt power from the communication link(e.g., inductive link) with the communications component 21 to anactuator associated with the valve of the channel 17 for repolarization.

IV. Methods

Another aspect of the present disclosure can include a method 30 forelectrically anesthetizing a peripheral nerve with on-demand electricalnerve block (OD-ENB) for chronic pain management (and/or the treatmentof other disorders), as shown in FIG. 3 . The method 30 can be executedusing the system 10 shown in FIGS. 1 . The implantable capsule 11delivers the OD-ENB to the patient using the blocking electrode 15 andblocking electrode contact 13 configured to deliver a direct current(DC) to a neural tissue (e.g., including one or more C fibers associatedwith pain) to block conduction, the return electrode 16 and returnelectrode contact 14 configured to receive the return DC from the nerve,and powering/communications component 18 configured to communicate withat least one external device 12 to at least receive a power signal. Theimplantable capsule 11 does not include a battery, causing theimplantable capsule 11 to be of a smaller size. Additionally, at leastthe blocking electrode contact 13, as well as the blocking electrode 15in some instances, are designed to avoid Faradaic reactions, likehydrogen evolution, oxygen evolution, chlorine evolution, or the like,when delivering the DC to the neural tissue. For example, the blockingelectrode 15 can utilize a saline interface. As another example, theblocking electrode 15 can utilize high capacitance electrode materials.Specific examples of electrodes that can be used as the blockingelectrode 15 include a separated interface nerve electrode (SINE), acarbon coated platinum electrode, a woven cloth carbon electrode, acarbon slurry electrode, or the like.

For purposes of simplicity, the method 30 is shown and described asbeing executed serially; however, it is to be understood and appreciatedthat the present disclosure is not limited by the illustrated order assome steps could occur in different orders and/or concurrently withother steps shown and described herein. Moreover, not all illustratedaspects may be required to implement the method 30, nor is the method 30necessarily limited to the illustrated aspects.

At Step 32, the capsule (e.g., implantable capsule 11, at least aportion of the capsule constructed of a conductive membrane and the restof the capsule comprises a biocompatible material) can be wirelesslypowered within the patient's body from an external power source (e.g.,within external component(s) 12). The powering/communications component18 can be configured to communicate with the external power source toreceive the power signal. Note that the external component can be usedfor powering/communication with a plurality of capsules. Thepowering/communications component 18 can also be configured to receiveand/or transmit information to the external component(s) 12 (as shownand described with respect to FIG. 2 ). In some instances, theimplantable capsule 11 can be injected into the patient's body inproximity to a target nerve (which can be chosen based on the conditioncausing pain).

At Step 34, the DC (either cathodic or anodic) can be delivered from thecapsule (e.g., implantable capsule 11) to neural tissue for a time. TheDC can provide the OD-ENB for at least the time. In some instances, theOD-ENB can last for a time period after the OD-ENB is turned off. Inother instances, the OD-ENB can be reversed quickly. The blockingelectrode contact 13 can be configured to deliver the DC (configured toblock conduction in the neural tissue to provide the OD-ENB) through aportion of the conductive membrane. In some instances, the blockingelectrode 15 can convert the DC to an ionic current delivered by theblocking electrode contact 13. The return electrode contact 14 can beconfigured to receive a return current from the neural tissue throughanother portion of the conductive membrane after the DC is applied.

From the above description, those skilled in the art will perceiveimprovements, changes and modifications. Such improvements, changes andmodifications are within the skill of one in the art and are intended tobe covered by the appended claims.

1-16. (canceled)
 17. A method comprising: wirelessly powering a capsulewithin a patient's body with a power signal from an external powersource, wherein at least a portion of the capsule constructed of aconductive membrane and the rest of the capsule comprises abiocompatible material, wherein the capsule comprises: a blockingelectrode contact configured to deliver a direct current (DC) through aportion of a conductive membrane, wherein the DC is configured to blockconduction in the neural tissue to provide on demand electrical nerveblock (OD-ENB); a return electrode contact configured to receive areturn current from the neural tissue through another portion of theconductive membrane; and a powering/communication component configuredto communicate with the external power source to receive the powersignal; and delivering the DC from the blocking electrode contact to theneural tissue for a time, wherein the DC causes the OD-ENB, wherein theOD-ENB is cathodic or anodic.
 18. The method of claim 17, furthercomprising receiving a return current by the return electrode contact inresponse to the DC being delivered from the blocking electrode contact.19. The method of claim 17, wherein a blocking electrode converts the DCto the ionic current delivered by the blocking electrode contact. 20.The method of claim 17, further comprising injecting the capsule intothe patient's body.
 21. The method of claim 17, wherein the capsule isan implantable capsule having an external shell.
 22. The method of claim17, wherein the other portion of the conductive membrane isnon-contiguous.
 23. The method of claim 17, further comprisingrecharging the blocking electrode contact and/or the return electrodecontact, wherein the blocking electrode contact and the return electrodecontact are each at least partially enclosed in sub-capsules within thecapsule that are connected by a channel for recharging.
 24. The methodof claim 23, wherein at least the blocking electrode contact comprises ahigh charge capacity material, a high capacitance slurry, and/or anionically conductive medium within the associated sub-capsule.
 25. Themethod of claim 24, further comprising providing the OD-ENB withoutproducing irreversible Faradaic reaction products at the neural tissue.26. The method of claim 17, further comprising receiving, at thepowering/communication component, an inductive power signal from theexternal power source, wherein the powering/communication componentcomprises an inductive coil and the external power source comprisesanother inductive coil.
 27. The method of claim 26, wherein the capsulefurther comprises an electrical component coupled to the inductive coil,the blocking electrode contact, and the return electrode contact. 28.The method of claim 27, further comprising configuring, by theelectrical component, the DC and delivering the DC to the blockingelectrode contact.
 29. The method of claim 17, wherein the blockingelectrode contact and the return electrode contact are located on a sameside of the capsule.
 30. The method of claim 17, wherein the blockingelectrode contact and the return electrode contact are located onopposite sides of the capsule.
 31. A method comprising: implanting acapsule within a patient's body, wherein the capsule comprises: ablocking electrode contact configured to deliver a direct current (DC)through a portion of a conductive membrane, wherein the DC is configuredto block conduction in the neural tissue to provide on demand electricalnerve block (OD-ENB); and a return electrode contact configured toreceive a return current from the neural tissue through another portionof the conductive membrane; and delivering the OD-ENB from the capsuleto the patient's body to electrically anesthetize a peripheral nervewithin the patient's body, wherein the OD-ENB is caused by a DC current.32. The method of claim 31, wherein the OD-ENB is used for painmanagement.
 33. The method of claim 31, further comprising wirelesslypowering the capsule within the patient's body with a power signal froman external power source.
 34. The method of claim 33, wherein thecapsule further comprises a powering/communication component configuredto communicate with the external power source to receive the powersignal.
 35. The method of claim 31, wherein at least a portion of thecapsule constructed of an external shell comprising a conductivemembrane and a biocompatible material.
 36. The method of claim 31,further comprising delivering the DC from the blocking electrode contactto the neural tissue for a time, wherein the DC is cathodic or anodic.